1. Technical Field
The invention relates to an electrophotographic photoreceptor for use in, for example, a copying machine that forms an image by an electrophotographic method, and a process cartridge and an image-forming apparatus using the electrophotographic photoreceptor.
2. Related Art
In recent years, the electrophotographic method has been used widely, for example, in copying machines and printers. An electrophotographic photoreceptor for use in image-forming apparatuses utilizing the electrophotographic method (hereinafter, sometimes referred to as a “photoreceptor”) comes into contact with various materials and is exposed to various stresses in the apparatus and thus deteriorates gradually. On the other hand, digitalization and colorization of image-forming apparatuses demand that the photoreceptor have high reliability.
Specifically, for example, the following issues can be mentioned in connection with the process of charging the photoreceptor. For example, in non-contact charging, discharge products deposit on the photoreceptor, which cause image blurring or the like. In order to remove the discharge products deposited on the photoreceptor, for example, a system in which particles having a polishing function are added to a developer and the developer is removed in a cleaning unit is used. However, in such a system, a surface of the photoreceptor is deteriorated gradually due to abrasion. In recent years, contact charging has been widely employed. However, the contact charging may accelerate abrasion of the photoreceptor as well.
Because of these issues, prolongation of the lifetime of electrophotographic photoreceptors has been required. In order to prolong the lifetime of electrophotographic photoreceptors, improvement in abrasion resistance is required, and thus increase in the hardness of a photoreceptor surface is needed.